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What's the difference between echo, print, and print_r in PHP?
...s you have in your variables. Consider this test program:
$values = array(0, 0.0, false, '');
var_dump($values);
print_r ($values);
With print_r you can't tell the difference between 0 and 0.0, or false and '':
array(4) {
[0]=>
int(0)
[1]=>
float(0)
[2]=>
bool(false)
[3]=...
How to add an empty column to a dataframe?
...t; df = pd.DataFrame({"A": [1,2,3], "B": [2,3,4]})
>>> df
A B
0 1 2
1 2 3
2 3 4
>>> df["C"] = ""
>>> df["D"] = np.nan
>>> df
A B C D
0 1 2 NaN
1 2 3 NaN
2 3 4 NaN
...
Convert int to char in java
...ascii value 49 (one corresponding to '1')
If you want to convert a digit (0-9), you can add 48 to it and cast, or something like Character.forDigit(a, 10);.
If you want to convert an int as in ascii value, you can use Character.toChars(48) for example.
...
SyntaxError: Use of const in strict mode
...
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How to send only one UDP packet with netcat?
...
205
If you are using bash, you might as well write
echo -n "hello" >/dev/udp/localhost/8000
a...
Python module os.chmod(file, 664) does not change the permission to rw-rw-r— but -w--wx----
...
130
Found this on a different forum
If you're wondering why that leading zero is important, it's...
HTML5 record audio to file
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107
There is a fairly complete recording demo available at: http://webaudiodemos.appspot.com/Audio...
Simple calculations for working with lat/lon and km distance?
...
The approximate conversions are:
Latitude: 1 deg = 110.574 km
Longitude: 1 deg = 111.320*cos(latitude) km
This doesn't fully correct for the Earth's polar flattening - for that you'd probably want a more complicated formula using the WGS84 reference ellipsoid (the model used ...
Regular expression for first and last name
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202
Don't forget about names like:
Mathias d'Arras
Martin Luther King, Jr.
Hector Sausage-Hausen
...